Amantadine Hydrochloride

Adults: Parkinson's disease, adults: The usual dose is 100 mg twice a day when used alone. The initial dose of Amantadine is 100 mg daily for patients with serious associated medical illnesses or who are receiving high doses of other antiparkinson drugs. After one to several weeks at 100 mg once daily, the dose may be increased to 100 mg twice daily, if necessary. Occasionally, patients whose responses are not optimal with Amantadine at 200 mg daily may benefit from an increase up to 400 mg daily in divided doses. Dosage for concomitant therapy: Some patients who do not respond to anticholinergic antiparkinson drugs may respond to Amantadine. When Amantadine or anticholinergic antiparkinson drugs are each used with marginal benefit, concomitant use may produce additional benefit. When Amantadine and levodopa therapy are initiated concurrently, the patient can exhibit rapid therapeutic benefits. Amantadine dose should be held constant at 100 mg daily or twice daily while the daily dose of levodopa is gradually increased to optimal benefit. When Amantadine is added to optimal well tolerated doses of levodopa, additional benefit may result, including smoothing out the fluctuations in improvement which sometimes occur in patients on levodopa alone. Patients who require a reduction in their usual dose of levodopa because of development of side effects may possibly regain lost benefit with the addition of Amantadine. Drug induced extrapyramidal reactions, adults: The usual dose is 100 mg twice a day. Occasionally, patients whose responses are not optimal with Amantadine at 200 mg daily may benefit from an increase up to 300 mg daily in divided doses. Prophylaxis and treatment of Influenza A virus illness, adults: 200 mg a day as a single dose or 100 mg twice daily. If CNS effects develop on a once daily dosage, a split dosage schedule may reduce complaints. Elderly over 65 years of age: 100 mg every day. Children 1 to 9 years of age: 4.4 to 8.8 mg/kg/day, not to exceed 150 mg/day. Children 9 to 12 years of age: 100 mg twice daily. Method of administration: Each capsule is to be taken orally either with or without food. Patients with renal impairment: The dose should be reduced. This can be achieved by either reducing the total daily dose, or by increasing the dosage interval in accordance with the creatinine clearance. Patients with hepatic impairment: Use with caution.